Shares drop 35 cents to $5.32, crimping its gain this year to 16%.
Total trades rise to 69,281 and the value of trading is up 66% to $2.3 billion.
Trading on the NZX's cash markets rise by a quarter in December as the NZX 50 Index rounds out its best year since 2004.
The pair will join the top 50 on December 24.
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